Biogen Idec (NASDAQ: BIIB) reported top-line results of EMPOWER, a Phase 3 trial investigating dexpramipexole in people with amyotrophic lateral sclerosis (ALS). The trial did not meet its primary endpoint, a joint rank analysis of function and survival, and no efficacy was seen in the individual components of function or survival. The trial also failed to show efficacy in its key secondary endpoints. Additional analyses of multiple subpopulations failed to demonstrate any efficacy among these groups. Based on these results, Biogen Idec will discontinue development of dexpramipexole in ALS.

"We share the disappointment of members of the ALS community, who had hoped that dexpramipexole would offer a meaningful new treatment option,” said Douglas E. Williams, Ph.D., Executive Vice President of Research and Development at Biogen Idec. “Nevertheless, the EMPOWER trial represents a significant contribution to ALS research, and Biogen Idec is committed to advancing ALS science. We continue to work with researchers around the world to understand the causes of ALS and find potential treatments for people with ALS.”

The company intends to present detailed results at a future medical conference.

EMPOWER Trial

EMPOWER was a randomized, double-blind, placebo-controlled Phase 3 trial which enrolled 943 people with ALS at 81 sites in 11 countries. Patients were randomized on a one-to-one basis to receive either dexpramipexole or placebo. The primary endpoint was a joint rank analysis of function and survival, known as the Combined Assessment of Function and Survival (CAFS). In addition to CAFS, the trial individually evaluated functional decline, survival and respiratory decline, among other measures.

“As a physician who has treated people with ALS, I hoped with all my heart for a different outcome,” said Douglas Kerr, M.D., Ph.D., Director of Neurodegeneration Clinical Research at Biogen Idec. “While these results were not what we expected, we hope these data will provide a foundation for future ALS research.”